During the “first flush” (i.e., the first fifteen (15) to twenty (20) minutes) of rainfall, a majority of loose sediments, oils and other pollutants are picked up and carried by rainwater off surfaces such as sidewalks, driveways and roadways. While the driving surface of most roadways typically allows for a predetermined spread of standing rainwater, there is a need to efficiently redistribute and control the flow of rainwater around the driving surface to minimize the risk of hydroplaning. Conventionally, rainwater is channeled, plumbed (and may even be pumped) away from the driving surface and into an oil/water separator, a separation tank, a retention pond, or a similar rainwater management or sediment separation device. The purposes of these devices is to control the allowable spread of standing rainwater on the driving surface, which increases the safe speed at which cars may move along the road, as well as to help keep fresh water sources clean and free of pollutants as the rainwater is recycled back into the water source system after it has been processed in some manner to remove pollutants. As used herein, “pollutants” comprise sediments, oils, debris, and other solids and chemicals found in surface water runoff.